Search results for "Electrode"
showing 10 items of 950 documents
Electroorganic synthesis of nitriles via a halogen-free domino oxidation–reduction sequence
2015
A direct electroorganic sequence yielding nitriles from oximes in undivided cells is reported. Despite the fact that intermediate nitrile oxides might be formed, the method is viable to prepare benzonitriles without substituents ortho to the aldoxime moiety. This constant current method is easy to perform for a broad scope of substrates and employs common electrodes, such as graphite and lead.
Label-free histamine detection with nanofluidic diodes through metal ion displacement mechanism
2017
[EN] We design and characterize a nanofluidic device for the label-free specific detection of histamine neurotransmitter based on a metal ion displacement mechanism. The sensor consists of an asymmetric polymer nanopore fabricated via ion track-etching technique. The nanopore sensor surface having metal-nitrilotriacetic (NTA-Ni2+) chelates is obtained by covalent coupling of native carboxylic acid groups with N-alpha,N-alpha-bis(carboxymethyl)-L-lysine (BCML), followed by exposure to Ni2+ ion solution. The BCML immobilization and subsequent Ni2+ ion complexation with NTA moieties change the surface charge concentration, which has a significant impact on the current-voltage (I-V) curve after…
Strain-induced improvement of retention loss in PbZr0.2Ti0.8O3 films
2015
The retention behavior of nanoscale domains in PbZr0.2Ti0.8O3 thin films is investigated by in-situ controlling the epitaxial strain arising from a piezoelectric substrate. The retention behavior in our sample shows strong polarity-dependence: Upward-poled domains exhibit excellent stability, whereas downward-poled domains reveal a stretched exponential decay. Reversible release of in-plane compressive strain strongly reduced the retention loss, reflected in an enhancement of the relaxation time by up to one order of magnitude. We tentatively attribute the observed behavior to a strain dependence of the built-in field at the interface to the La0.7Sr0.3MnO3 bottom electrode, with a possible …
Supercontinuum optimization for dual-soliton based light sources using genetic algorithms in a grid platform
2014
We present a numerical strategy to design fiber based dual pulse light sources exhibiting two predefined spectral peaks in the anomalous group velocity dispersion regime. The frequency conversion is based on the soliton fission and soliton self-frequency shift occurring during super- continuum generation. The optimization process is carried out by a genetic algorithm that provides the optimum input pulse parameters: wavelength, temporal width and peak power. This algorithm is implemented in a Grid platform in order to take advantage of distributed computing. These results are useful for optical coherence tomography applications where bell-shaped pulses located in the second near-infrared wi…
Detector-electrode for alpha spectrometry in water sample, numerical and early feasibility investigation toward thermocompression bonding assembly pr…
2020
International audience; This study focuses on the feasibility of a detector-electrode for direct alpha measurement in aqueous samples. Such a device could be made by adding a boron doped diamond electrode on top of a standard silicon detector, with bonding and insulating layers. The impact of these different layers has been investigated by Monte-Carlo simulation (MCNP6), to find a compromise between alpha detection of the silicon, electrode and shielding properties of the diamond. The assembly process involving thermocompression between both substrates was successfully achieved under a clean room conditions.
Multi-technique characterization of gold electroplating on silver substrates for cultural heritage applications
2017
Proceedings of the 12th European Conference on Accelerators in Applied Research and Technology (ECAART12).-- et al.
Microbeam SEE Analysis of MIM Capacitors for GaN Amplifiers
2018
Broad-beam and microbeam single-event effect tests were performed on metal–insulator–metal capacitors with three different thicknesses of silicon nitride (Si3N4) dielectric insulator: 250, 500, and 750 nm. The broad-beam tests indicated that the devices with the thicker, 500- and 750-nm dielectric did not have a greater breakdown voltage. The surrounding structures of the capacitor were suspected to be a possible cause. Microbeam techniques made it possible to localize the failure location for the 500- and 750-nm devices. The failure occurs in the air bridge structure connected to the top capacitor plate, which can therefore be considered as an edge effect, while for the 250-nm devices, the…
Vacuum electrical breakdown conditioning study in a parallel plate electrode pulsed dc system
2019
Conditioning of a metal structure in a high-voltage system is the progressive development of resistance to vacuum arcing over the operational life of the system. This is, for instance, seen during the initial operation of radio frequency (rf) cavities in particle accelerators. It is a relevant topic for any technology where breakdown limits performance and where conditioning continues for a significant duration of system run time. Projected future linear accelerators require structures with accelerating gradients of up to 100 MV/m. Currently, this performance level is achievable only after a multimonth conditioning period. In this work, a pulsed dc system applying voltage pulses over paral…
Radiation hard monolithic CMOS sensors with small electrodes for High Luminosity LHC
2019
Abstract The upgrade of the tracking detectors for the High Luminosity-LHC (HL-LHC) requires the development of novel radiation hard silicon sensors. The development of Depleted Monolithic Active Pixel Sensors targets the replacement of hybrid pixel detectors with radiation hard monolithic CMOS sensors. We designed, manufactured and tested radiation hard monolithic CMOS sensors in the TowerJazz 180 nm CMOS imaging technology with small electrodes pixel designs. These designs can achieve pixel pitches well below current hybrid pixel sensors (typically 50 × 50 μ m ) for improved spatial resolution. Monolithic sensors in our design allow to reduce multiple scattering by thinning to a total si…
Cooling of the plasma chamber for the AECR-U type electron cyclotron resonance ion source ARTEMIS
2001
Abstract The temperature distribution inside the ECRIS plasma chamber has been studied using finite element analysis. The main goal of these studies was to find out the safest cooling design for the temperature sensitive permanent magnets. In ECR ion sources they are used to provide the hexapole field. Two different designs for the cooling of the magnets were investigated. The temperature distribution on the surface of the plasma electrode was also studied. With the aid of the cooling simulations the most efficient cooling for the new ECR ion source was found. As a result of which, safety and higher reliability of operation can be reached.